Underground storage tank

Abstract

Underground storage tank consisting of an internal metal structure (1), of a static external facing (2) and of a filler (4) such a hot blown bitumen located between the metal structure (1) and the static facing (2), the outer surface of the metal structure (1) presenting welded structural shapes (7) properly spaced and cross connected to increase the bond between the metal structure (1) and the filler (4).

I claim: 
     
       1. An underground liquid storage tank, comprising: (a) an annular metal liner extending along a generally longitudinal axis, said liner including a plurality of curved plates having interior surfaces bounding a liquid storage chamber, and exterior surfaces located opposite the interior surfaces;   (b) an annular concrete facing concentric with said axis, surrounding the liner, and bounding an annular space with the exterior surfaces of the plates;   (c) a plurality of structural elements fixedly mounted on the exterior surfaces of the plates and located within said annular space; and   (d) a viscous, settable, elastic filler filling said annular space and encapsulating the elements therein to form a strengthened elastic bond between the liner and the filler.   
     
     
       2. The tank according to claim 1, wherein the elements are metal and are welded onto the plates. 
     
     
       3. The tank according to claim 1, wherein the elements are spaced apart along said axis. 
     
     
       4. The tank according to claim 1, wherein the elements are co-linear along said axis. 
     
     
       5. The tank according to claim 1, wherein at least one of the elements extends transversely of said axis. 
     
     
       6. The tank according to claim 1, wherein the filler is a bitumen pourable into said annular space at a temperature ranging from about 200° C. to about 220° C.